deno-lambda VS bun

Using Deno with AWS Lambda functions requires a custom runtime. You can build your own runtime or use one that already exists. If you’re concerned about security, I suggest maintaining a copy of an existing runtime and carefully inspecting updates or creating your own runtime. For this proof of concept, I deployed the Serverless Application Repository (SAR) app for Deno into my AWS account. I used the included Lambda layer and the provided.al2 Lambda runtime to create my Deno Lambda function. I created a file called index.ts with some basic JavaScript code that makes requests to two different websites and returns the HTTP status code of the response or a caught error. I then updated the function’s configuration to reference the exported handler function.

I'm doing a simple PoC / testing with Deno using https://github.com/hayd/deno-lambda and specifically the CDK instructions.

As I had mentioned, it requires using a Lambda Layer. See: https://github.com/hayd/deno-lambda/blob/2d90756a0f18b57f16e...

Using your own image (i.e. without using the base AWS image with the layer) you'd get even worse cold start times.

Decorators and TypeScript aren't supported out of the box in Lambda (without using deno) so we'll also need a transpilation step if we go this route. Fortunately this is a mostly solved problem for AWS CDK, AWS SAM and Serverless Framework users. If you want or need to roll your own, esbuild is a great place to start and seems to be the bundler of choice for this purpose.

In addition to the stuff posted here, there's the deno-lambda project for deploying to AWS Lambda

Cloud hosting support. Deno runs fine in a container, but lambda/cloud function support is difficult on most providers. deno-lambda exists but it only applies to AWS and can't be used with all CICD tools. Deno Deploy also exists but it's pretty new.

It has a decent compatibility with both Jest and Vitest's APIs (you can track progress here so you can use it as almost a drop-in replacement for either. Just as Node's, it has describe/it, mock, test and others, but with the expect syntax (which I find more readable). For example:

In this third and final article in the series on HTML Streaming, we will explore the practical implementation of the Diff DOM Streaming library in web browsing. This approach will allow any website using web components to retain its state during browsing. We will discuss in detail how to achieve this step by step using VanillaJS and Bun.

At Node Conference 2023, Jarred Sumner (creator of Bun) showed a demo of server components in Bun, so there is at least partial support in that ecosystem. The Bun repo provides bun-plugin-server-components as the official plugin for server components. And while I haven’t looked at it in-depth, Marz claims to be a “React Server Components Framework for Bun”.

Continuously evolving, Bun is currently optimized for MacOS and Linux, with ongoing efforts towards Windows compatibility. Tailored for resource-constrained environments like serverless functions, it emerges as an ideal solution. The Bun team is committed to achieving comprehensive Node.js compatibility and seamless integration with prevalent frameworks. For those intrigued by Bun's potential and want to give it a try, more information is available on its website at https://bun.sh/.

Let’s say you are interested in learning more about Bun and probably give it a try. Bun has a website, where you can learn more about Bun and its features (including all the benchmark data captured in this issue), and here is the link.

Looks like it, it seems the 2% are mostly odd platform specific issues that the authors' did not deem very important (my assumption for the release happening anyway). AFAIK this[1] PR tries to fix them.

[1]: https://github.com/oven-sh/bun/pull/9729

Bun has a solution for it. First of all, it already has a list of trusted dependencies. For them, Bun will execute all necessary scripts by default. Otherwise, you can add it to trustedDependecies in your package.json file. In Bun community usage of trustedDependencies is a hot topic. There are several suggestions on how to improve it.

Install Node.js (or Bun, or Deno, or whatever JS runtime you prefer) if it's not there

I think maybe I was unclear. I'm talking about writing libraries that abstract across these differences and provide a single API, as sibling describes. I already know it's possible. I made a simple filesystem abstraction here[0] and a very simple HTTP library that uses it here[1]. They both work in Node/Deno and the browser. Unfortunately I ran into issues with Bun's slice implementation[2]. But I suspect there's a much better way of detecting and using the different backends.

[0]: https://github.com/waygate-io/fs-js

[1]: https://github.com/waygate-io/http-js

[2]: https://github.com/oven-sh/bun/issues/7057